


Area Forecast Discussion
Issued by NWS Denver/Boulder, CO
Issued by NWS Denver/Boulder, CO
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010 FXUS65 KBOU 240647 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1247 AM MDT Tue Jun 24 2025 .KEY MESSAGES... - Cooler with more moisture and scattered to likely showers and thunderstorms Monday through Wednesday. - Severe storms possible across the plains Tuesday, with large hail and gusty outflow winds being the main threat. - Drier Thursday through Sunday with warming temperatures and only isolated late day showers and thunderstorms. && .DISCUSSION /Through Monday/... Issued at 258 PM MDT Mon Jun 23 2025 Skies over the urban corridor certainly had a case of the "Mondays" today, with a blanket of low clouds remaining in place through the morning. With the low ceilings in place, solar heating has been limited, resulting in a later start to convective initiation than previously expected. While ACARS soundings still show a hefty cap in place over the plains at the time of this writing, some cumulus have started to show some upwards growth over portions of the high country, with even a few flashes of lightning seen in the latest satellite imagery. Guidance has been persistent in showing that storms will eventually make their way off the higher terrain, but we still have a few hours to go before this is expected to occur. Due to the delay, higher PoPs were pushed back a few hours this forecast package, with increasing PoPs now expected around 0Z (6PM) for the urban corridor, before spreading eastward through the evening. The SPC has put southern Lincoln County in a Marginal Risk for severe storms this evening, with damaging outflow wind gusts and marginal sized hail being the main threats. Southwesterly flow aloft will be in place on Tuesday, with a near 100 kt jet crossing the Rockies from SW to NE, with the forecast area expected to be in decent proximity to it`s right entrance region, though not under its strongest influences. A disturbance in the 500 mb flow is expected to traverse the Rockies Tuesday, providing lift come the afternoon. At the 700 mb level, Gulf moisture will be pulled into eastern Colorado as it wraps around a high over the southeastern US. Dewpoint temperatures are expected to climb into the 60s, and with inverted-v forecast soundings showing MLCAPE between 900 to 1000 J/kg, mid-level lapse rates surpassing 7 C/km, and DCAPE over 1000 J/kg, severe storms will be possible for our lower elevations for the afternoon/evening. With marginal shear being the limiting factor for more organized storms to develop, hail and gusty outflow winds are the main threats with these storms, with tornadoes having the lowest expected hazard potential, yet can`t be ruled out. We are expecting to see convection develop early afternoon, with severe storms possible across the urban corridor and Palmer Divide first, before pushing eastward through the afternoon and evening. The SPC has put the majority of our lower elevations in a Slight Risk for tomorrow, for concern of storms capable of producing 2"+ hail and winds surpassing 60 mph. Unsettled weather will continue on Wednesday afternoon, with isolated to scattered afternoon thunderstorms likely initiating over the mountains and pushing east onto the plains once again. There will still be a chance for a few more organized storms to develop, but the severe threat is expected to be less than Tuesday`s. Warmer and drier conditions are expected to return for the latter half of the week, with 90s returning to the lower elevations by Friday. && .AVIATION /06Z TAFS through 06Z Wednesday/... Issued at 1244 AM MDT Tue Jun 24 2025 Ceilings between 1500 and 4000 ft are expected to become widespread in the early morning hours, then break up between 16z and 18z. Scattered thunderstorms are expected between 19z and 24z. Variable winds gusting to 30 knots and brief ceiling and visibility restrictions will be the main impacts, but a severe storm with large hail and 50 knot gusts is possible at KDEN and KAPA. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Bonner AVIATION...Gimmestad